James stewart



UNITED STATES PATENT OFFICE.

JAMES STEWVART, OF NEW YORK, N. Y., ASSIGNOR OFONE-HALF TO EDMUND O. STANTON, OF SAME PLACE.

ELECTRIC-LAMP ADAPTER.

SPECIFICATION forming part of Letters Patent No. 420,705, dated February 4, 1890.

Application filed August 4, 1888. Serial No. 281,956. (No model.)

ToaZZ whom it may concern:

Be it known that I, JAMES STEWART, of the city, county, and State of New York, have invented a new and Improved Electric-Lamp Coupler or Adapter, of which the following is a specification, reference being had to the anneXed drawings, forming a part thereof, in which- Figure 1 is a plan view of my improved lamp coupler or adapter. Fig. 2 is a plan view of the same with the top removed. Fig. 3 is a transverse section taken on line 00 a: in Fig. 1. Fig. 4. is a perspective view of the lamp coupler oradapier and a portion of a lamp fitted to the same. Fig. 5 is a plan view of a modified form of my improved lamp coupler or adapter. Fig. 6 is a perspective view of a socket for receiving the same. Fig. 7 is a plan view of the said socket. Fig. 8 is an inverted plan view of a modified form of socket. Fig. 9 is a transverse section taken on line m in Fig. 8. Fig. 10 is a plan view of a socket fitted to the adapter shown in Fig. 8, and Fig. 11 is a side elevation of a lamp and socket.

Similar letters of reference indicate corresponding parts in all the views.

The object of my invention is to construct a device for coupling or adapting a lamp having terminals formed of studs provided with heads to sockets of different kinds.

My improvement consists in a cup-shaped disk of insulating material provided with forked springs connected with electrodes capable of contacting with the electrodes of the socket, the said disk having key-slots for receiving the studs of a lamp and guiding them to engagement with the forked springs, all as hereinafter more fully described.

The lamp-base A (shown in Fig. 4) is provided with terminals consisting of headed studs a.

The coupler or adapter shown in Fig. 1 consists of acup-shaped button B, formed of insulating material and provided with curved forked springs O. The springs 0 near their ends are bowed outwardly, and their extremities are bent in opposite directions, to facilitate the entrance between the halves of the springs of the studs a of the lamp. The springs C are held in place in recesses therefor in the cupshaped button B by a cover D, in which are inserted two screws 5 b, which are inserted in bosses formed on the heels of the springs C. The screw 1) contacts with a lug 0, formed on the metallic ring d, surrounding the button and adapted to fit into a screw-threaded metallic lamp-socket, and the screwb forms an electrical connection only with the spring 0, into which it is screwed. The cover D and base of the button B are provided with curved oblong apertures for receiving the studs a. The button B is inserted in a socket provided with springs adapted to touch the screws 1) b, and the lamp is secured in the socket by first inserting the studs a into the slots 6, then turning the lamp so as to bring the studs into engagement with the curved springs C. Fig. t shows the edge and under surface of this form of adapter.

When the coupler or adapter is to be applied to a socket wit-h a bayonet-joint fastening, as shown in Figs. 6 and 7, screws f are inserted in the periphery of the button at diametrically-opposite points for engagement with the L-shaped slots 9 in the socket.

In the coupler or adapter shown in Fig. 2 the spring C is connected with the metallic rim (1, surrounding. the button B, and the spring 0 is connected with a central screw h, which projects below the surface of the button and is adapted to engage the central contact-spring 2' of the socket shown in Fig. 10. The metallic peripheryof the button B in this case forms an electrical contact with the metallic part of the socket. The sides of the button are apertu'red as in the other case, and the lamp is inserted and secured in the same manner as before.

\Vhen a coupler or adapter of the kind shown in Fig. 1 is to be applied to the socket shown in Fig. 10, the screwb is removed and replaced by a screw 11*, having a beveled head, which clamps to the upper surface of the button B an arm havinga contact-piece 7.: attached to the inner end thereof opposite the center of the button, thus forming a connection with one of the springs CI The screw 1) is replaced by a screw b the head of which is countersunk into and clamps a metallic segment lto the bottom of the button, which extends up I00 the side of the button and forms an electrical connection with the internally-threaded part of the lamp-socket.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- In an electric-lamp adapter, the combination, with a chambered button of insulatingmaterial, of two curved forked springs placed 111 the chambers of the button and oppositely arranged with respect to each other, the said button being furnished at the periphery and bottom with electrical contacts connected with the curved forked springs and constructed to enter into and form electrical connections with the lamp-socket, substantially as speciiied.

JAMES STEYVAR'I.

Witnesses;

E. M. CLARK, 0. SEDGWIOK. 

